Battery pack and method of assembling the battery pack

ABSTRACT

A battery pack having a battery pack housing defining an interior region is provided. The housing further includes an inlet aperture and an outlet aperture communicating with the interior region. The battery pack further includes a battery module that is disposed in the interior region of the battery pack housing proximate to the inlet aperture. The battery module has a first battery cell, a heat exchanger, and first and second end plates. The first battery cell and the heat exchanger are disposed against one another, and are further disposed between the first and second end plates. The heat exchanger defines a first flow path portion therethrough. The first end plate has a first end portion that extends longitudinally past the first end of the first battery cell, and a second end portion that extends longitudinally past the second end of the first battery cell.

BACKGROUND

The inventors herein have recognized a need for an improved battery packand a method of assembling the battery pack.

SUMMARY

A battery pack in accordance with an exemplary embodiment is provided.The battery pack includes a battery pack housing defining an interiorregion. The battery pack housing further includes an inlet aperture andan outlet aperture communicating with the interior region. The batterypack further includes a battery module that is disposed in the interiorregion of the battery pack housing proximate to the inlet aperture. Thebattery module has a first battery cell, a heat exchanger, and first andsecond end plates. The first battery cell and the heat exchanger aredisposed against one another, and are further disposed between the firstand second end plates. The heat exchanger defines a first flow pathportion therethrough. The first battery cell has a first end and asecond end. The first end plate extends substantially parallel to alongitudinal axis of the battery module toward the inlet aperture. Thefirst end plate has a first end portion and a second end portion. Thefirst end portion of the first end plate extends longitudinally past thefirst end of the first battery cell. The second end portion of the firstend plate extends longitudinally past the second end of the firstbattery cell. The second end plate extends substantially parallel to thelongitudinal axis of the battery module. The second end plate has afirst end portion and a second end portion. The first end portion of thesecond end plate extends longitudinally past the first end of the firstbattery cell toward the inlet aperture. The second end portion of thesecond end plate extends longitudinally past the second end of the firstbattery cell. The battery pack further includes a thermally conductivehousing that is disposed in the interior region of the battery packhousing between the battery module and the outlet aperture of thebattery pack housing. The thermally conductive housing defines a secondflow path portion between the thermally conductive housing and thebattery pack housing. The second flow path portion fluidly communicateswith the first flow path portion. The battery pack further includes anelectric fan disposed in the interior region of the battery packhousing. The electric fan is adapted to urge air to flow through theinlet aperture and through the first and second flow path portions andfurther through a portion of the electric fan and through the outletaperture of the battery pack housing.

A method for assembling a battery pack in accordance with anotherexemplary embodiment is provided. The method includes providing abattery pack housing, a battery module, a thermally conductive housing,and an electric fan. The battery pack housing defines an interiorregion. The battery pack housing further includes an inlet aperture andan outlet aperture communicating with the interior region. The batterymodule has a first battery cell, a heat exchanger, and first and secondend plates. The first battery cell and the heat exchanger are disposedagainst one another, and are further disposed between the first andsecond end plates. The heat exchanger defines a first flow path portiontherethrough. The first battery cell has a first end and a second end.The first end plate extends substantially parallel to a longitudinalaxis of the battery module. The first end plate has a first end portionand a second end portion. The first end portion of the first end plateextends longitudinally past the first end of the first battery cell. Thesecond end portion of the first end plate extends longitudinally pastthe second end of the first battery cell. The second end plate extendssubstantially parallel to the longitudinal axis of the battery module.The second end plate has a first end portion and a second end portion.The first end portion of the second end plate extends longitudinallypast the first end of the first battery cell. The second end portion ofthe second end plate extends longitudinally past the second end of thefirst battery cell. The method further includes disposing the batterymodule in the interior region of the battery pack housing proximate tothe inlet aperture. The method further includes disposing the thermallyconductive housing in the interior region of the battery pack housingbetween the battery module and the outlet aperture of the battery packhousing. The thermally conductive housing defines a second flow pathportion between the thermally conductive housing and the battery packhousing. The second flow path portion fluidly communicates with thefirst flow path portion. The method further includes disposing theelectric fan in the interior region of the battery pack housing. Theelectric fan is adapted to urge air to flow through the inlet apertureand through the first and second flow path portions and further througha portion of the electric fan and through the outlet aperture of thebattery pack housing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of a battery pack in accordance with an exemplaryembodiment;

FIG. 2 is another schematic of the battery pack of FIG. 1;

FIG. 3 is a partially transparent top view of the battery pack of FIG.1;

FIG. 4 is a partially transparent bottom view of the battery pack ofFIG. 1;

FIG. 5 is a schematic of a base portion of a battery pack housingutilized in the battery pack of FIG. 1;

FIG. 6 is a cross-sectional schematic of the battery pack of FIG. 1;

FIG. 7 is a schematic of a battery module utilized in the battery packof FIG. 1;

FIG. 8 is another schematic of the battery module of FIG. 7;

FIG. 9 is a cross-sectional schematic of the battery module of FIG. 7taken along lines 9-9;

FIG. 10 is a cross-sectional schematic of the battery module of FIG. 7taken along lines 10-10;

FIG. 11 is an exploded view of a portion of the battery module of FIG.7;

FIG. 12 is a schematic of a first side of the battery module of FIG. 7illustrating ends of first, second, and third heat exchangers;

FIG. 13 is a schematic of a second side of the battery module of FIG. 7illustrating ends of first, second, and third heat exchangers;

FIG. 14 is a schematic of a frame member utilized in the battery moduleof FIG. 7;

FIG. 15 is another schematic of the frame member of FIG. 14;

FIG. 16 is another schematic of the frame member of FIG. 15;

FIG. 17 is a side view of the frame member of FIG. 15 illustrating anend of a heat exchanger;

FIG. 18 is a schematic of a first side of the frame member of FIG. 15;

FIG. 19 is a schematic of a second side of the frame member of FIG. 15;

FIG. 20 is a schematic of a first side of a first thermally conductiveplate utilized in a heat exchanger in the frame member of FIG. 15;

FIG. 21 is a schematic of a second side of the first thermallyconductive plate of FIG. 20;

FIG. 22 is a schematic of a first side of a second thermally conductiveplate utilized in a heat exchanger in the frame member of FIG. 15;

FIG. 23 is a schematic of a thermally conductive housing utilized in thebattery pack of FIG. 1;

FIG. 24 is another schematic of the thermally conductive housing of FIG.23;

FIG. 25 is a schematic of a bottom side of the thermally conductivehousing of FIG. 23;

FIG. 26 is another schematic of the thermally conductive housing of FIG.23;

FIG. 27 is a flowchart of a method of assembling a battery module inaccordance with another exemplary embodiment; and

FIG. 28 is a flowchart of a method of assembling a battery pack inaccordance with another exemplary embodiment.

DETAILED DESCRIPTION

Referring to FIGS. 1-6, a battery pack 10 in accordance with anexemplary embodiment is provided. The battery pack 10 includes a batterypack housing 30, a battery module 34, a thermally conductive housing 38,a DC/DC voltage converter 42, and an electric fan 46. An advantage ofthe battery pack 10 is that the battery pack 10 has the battery module34 with end plates 230, 232 that extend past internal battery cells todirect air into heat exchangers contacting the battery cells. Thus, thebattery pack 10 does not need a separate air manifold to direct air intoheat exchangers contacting the battery cells.

Referring to FIGS. 1, 2 and 5, the battery pack housing 30 is providedto hold the remaining components of the battery pack 10 therein. Thebattery pack housing 30 has a base portion 70 and an upper cover 72which define an interior region 74. The interior region 74 includes aninterior space 76 and an interior space 78.

Referring to FIG. 5, the base portion 70 includes a bottom wall 90 andside walls 92, 94, 96, 98. The side walls 92, 94, 96, 98 are coupled tothe bottom wall 90 and extend upwardly substantially perpendicular tothe bottom wall 90. The side walls 92, 94 extend substantially parallelto one another. Further, the side walls 96, 98 extend substantiallyparallel to one another and perpendicular to the side walls 92, 94. Theside wall 92 includes an inlet aperture 112 extending therethrough, andthe side wall 94 includes an outlet aperture 114 extending therethrough.In an exemplary embodiment, the base portion 70 is constructed of steelor aluminum. In an alternative embodiment, the base portion 70 isconstructed of plastic.

The upper cover 72 is removably coupled to the side walls 92, 94, 96, 98to enclose the interior region 74. In an exemplary embodiment, the uppercover 72 is constructed of steel or aluminum. In an alternativeembodiment, the upper cover 72 is constructed of plastic.

Referring to FIGS. 5-11, the battery module 34 is disposed in theinterior space 76 of the interior region 74 of the battery pack housing30 proximate to the inlet aperture 112. The battery module 34 includesframe members 120, 124, 128, an insulating layer 140, battery cells 150,154, 158, 162, 166, 170, 180, 184, 188, 192, 196, 200, battery cellinterconnect assemblies 220, 222, and end plates 230, 232.

Referring to FIGS. 7, 9, and 10, the frame members 120, 124, 128 areprovided to hold the battery cells 150-200 therebetween. The framemember 124 is coupled to and between the frame members 120, 128. Thestructure of each of the frame members 120, 124, 128 are identical toone another. Accordingly, only the structure of the frame member 120will be described in detail below.

Referring to FIGS. 14-21, the frame member 120 has a substantiallyrectangular ring-shaped outer plastic frame 260, central plastic walls262, 263, and a heat exchanger 264. The heat exchanger 264 has first andsecond thermally conductive plates 360, 362 that are coupled togetherand define a flow path portion 540 that extends therethrough. Referringto FIG. 17, the flow path portion 540 has flow path subportions 550,552, 554, 556, 558, 560 each extending through the first and secondthermally conductive plates 360, 362.

Referring to FIGS. 14-16, the substantially rectangular ring-shapedouter plastic frame 260 is coupled around an outer peripheral region ofthe first and second thermally conductive plates 360, 362. The firstsubstantially rectangular ring-shaped outer plastic frame 360 has first,second, third, and fourth side walls 280, 282, 284, 286. The first andsecond side walls 280, 282 extend substantially parallel to one another.The third and fourth side walls 284, 286 are coupled between the firstand second side walls 280, 282 and extend substantially parallel to oneanother and perpendicular to the first and second side walls 280, 282.

The central plastic wall 262 extends between the third and fourth sidewalls 284, 286 substantially parallel to the first and second side walls280, 282. The central plastic wall 262 is disposed on a portion of thefirst side 380 (shown in FIG. 20) of the thermally conductive plate 360of the heat exchanger 264.

The central plastic wall 263 extends between the third and fourth sidewalls 284, 286 substantially parallel to the first and second side walls280, 282. The central plastic wall 263 is disposed on a portion of thefirst side 480 (shown in FIG. 22) of the thermally conductive plate 362of the heat exchanger 264.

The first, third, and fourth side walls 280, 284, 286 and the centralplastic wall 262 define a region for receiving a battery cell therein.The second, third, and fourth side walls 282, 284, 286 define a regionfor receiving another battery cell therein.

The first side wall 280 has apertures 300, 302, 304 extendingtherethrough. The aperture 300 fluidly communicates with the flow pathsubportions 550, 552. Also, the aperture 302 fluidly communicates withthe flow path subportions 554, 556. Further, the aperture 304 fluidlycommunicates with the flow path subportions 558, 560.

Referring to FIG. 17, the second side wall 282 has apertures 310, 312,314 extending therethrough. The aperture 310 fluidly communicates withthe flow path subportions 550, 552. Also, the aperture 312 fluidlycommunicates with the flow path subportions 554, 556. Further, theaperture 314 fluidly communicates with the flow path subportions 558,560.

Referring to FIGS. 14 and 15, the third side wall 284 has grooves 320,322, 324, 326 extending therein. The fourth side wall 286 has grooves330, 332, 334, 336 extending therein. The grooves 320, 330 areconfigured to receive first and second electrical terminals of a batterycell therethrough. Further, the grooves 324, 334 are configured toreceive first and second electrical terminals of another battery celltherethrough. Still further, the grooves 322, 332 are configured toreceive first and second electrical terminals of another battery celltherethrough. Finally, the grooves 326, 336 are configured to receivefirst and second electrical terminals of another battery celltherethrough.

Referring to FIGS. 20-22, the heat exchanger 264 includes first andsecond thermally conductive plates 360, 362 that are coupled togetherand define the flow path portion 540 extending completely through theplates 360, 362.

The first thermally conductive plate 360 includes a sheet portion 370having a first side 380 and a second side 382. The sheet portion 370includes elongated depressed portions 390, 392, 394, 396, 398, 400, 402,404, 406, 408, and depressed edge portions 410, 412. In an exemplaryembodiment, the sheet portion 370 is constructed of aluminum and issubstantially rectangular-shaped.

The second thermally conductive plate 362 includes a sheet portion 470having a first side 480 and a second side 482. The sheet portion 470includes elongated depressed portions 490, 492, 494, 496, 498, 500, 502,504, 506, 508, and depressed edge portions 510, 512. In an exemplaryembodiment, the sheet portion 470 is constructed of aluminum and issubstantially rectangular-shaped.

The first thermally conductive plate 360 is coupled to the secondthermally conductive plate 362 such that the elongated depressedportions 390, 392, 394, 396, 398, 400, 402, 404, 406, 408 contact andare coupled to the elongated depressed portions 490, 492, 494, 496, 498,500, 502, 504, 506, 508, respectively and the depressed edge portions410, 412 contact and are coupled to the depressed edge portions 510,512. The plates 360, 362 define the flow path portion 540 having theflow path subportions 550, 552, 554, 556, 558, 560 that extendingentirely through a longitudinal length of the plates 360, 362.

Referring to FIG. 7, the frame member 124 has an identical structure asthe frame member 120 described above. The frame member 124 has asubstantially rectangular ring-shaped outer plastic frame 570, first andsecond central plastic walls (not shown), and a heat exchanger 572.

The frame member 128 has an identical structure as the frame member 120described above. The frame member 128 has a substantially rectangularring-shaped outer plastic frame 580, first and second central plasticwalls (not shown), and a heat exchanger 582.

Referring to FIGS. 6, 9 and 10, the frame member 120 and the end plate232 are configured to hold the battery cells 150, 180 therebetween.Further, the heat exchanger 264 of the frame member 120 is disposedbetween and contacts the battery cells 150, 154. Also, the heatexchanger 264 is disposed between and contacts the battery cells 180,184.

The frame members 120, 124 are configured to hold the battery cells 154,158 therebetween. Further, the frame members 120, 124 are configured tohold the battery cells 184, 188 therebetween. The heat exchanger 572 ofthe frame member 124 is disposed between and contacts the battery cells158, 162. Also, the heat exchanger 572 is disposed between and contactsthe battery cells 188, 192.

The frame members 124, 128 are configured to hold the battery cells 162,166 therebetween. Further, the frame members 124, 128 are configured tohold the battery cells 192, 196 therebetween. The heat exchanger 582 ofthe frame member 128 is disposed between and contacts the battery cells166. 170. Also, the heat exchanger 582 is disposed between and contactsthe battery cells 196, 200.

The frame member 128 and the insulating layer 140 (shown in FIG. 9) areconfigured to hold the battery cells 170, 200 therebetween. The heatexchanger 582 of the frame member 128 is disposed against the batterycells 170, 200. The end plate 230 is coupled to the frame member 128such that the insulating layer 140 is disposed between the frame member128 and the battery cells 170, 200.

The battery cells 150, 154, 158, 162, 166, 170, 180, 184, 188, 192, 196,200 are each configured to generate an operational voltage. In oneexemplary embodiment, the battery cells 150-200 are pouch-typelithium-ion battery cells that have a substantially rectangular-shapedbody portion and a pair of electrical terminals. In an exemplaryembodiment, the battery cells 150-200 are electrically coupled in serieswith one another utilizing interconnect members on the battery cellinterconnect and voltage sensing assemblies 220, 222. Further, in anexemplary embodiment, the electrical terminals of the battery cells150-200 are coupled to corresponding interconnect members byultrasonically welding the electrical terminals of the battery cells150-200 to the corresponding interconnect members utilizing anultrasonic welding machine. The structure of the battery cells 150-200are identical to one another.

Referring to FIG. 9, the battery cell 150 has a rectangular-shapedhousing 640 with electrical terminals 642, 644, extending from first andsecond ends, respectively, of the housing 640. The electrical terminal642 is electrically and physically coupled to the battery cellinterconnect and voltage sensing assembly 220. The electrical terminal644 is electrically and physically coupled to the battery cellinterconnect and voltage sensing assembly 222.

The battery cell 154 has a rectangular-shaped housing 650 withelectrical terminals 652, 654, extending from first and second ends,respectively, of the housing 650. The electrical terminal 652 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 654 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The battery cell 158 has a rectangular-shaped housing 660 withelectrical terminals 662, 664, extending from first and second ends,respectively, of the housing 660. The electrical terminal 662 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 664 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The battery cell 162 has a rectangular-shaped housing 670 withelectrical terminals 672, 674, extending from first and second ends,respectively, of the housing 670. The electrical terminal 672 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 674 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The battery cell 166 has a rectangular-shaped housing 680 withelectrical terminals 682, 684, extending from first and second ends,respectively, of the housing 680. The electrical terminal 682 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 684 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The battery cell 170 has a rectangular-shaped housing 690 withelectrical terminals 692, 694, extending from first and second ends,respectively, of the housing 690. The electrical terminal 692 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 694 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The series combination of the battery cells 150-170 are electricallycoupled in series with the series combination of the battery cells180-200 utilizing an elongated interconnect member.

Referring to FIG. 10, the battery cell 180 has a rectangular-shapedhousing 700 with electrical terminals 702, 704 extending from first andsecond ends, respectively, of the housing 700. The electrical terminal702 is electrically and physically coupled to the battery cellinterconnect and voltage sensing assembly 220. The electrical terminal704 is electrically and physically coupled to the battery cellinterconnect and voltage sensing assembly 222.

The battery cell 184 has a rectangular-shaped housing 710 withelectrical terminals 712, 714 extending from first and second ends,respectively, of the housing 710. The electrical terminal 712 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 714 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The battery cell 188 has a rectangular-shaped housing 720 withelectrical terminals 722, 724 extending from first and second ends,respectively, of the housing 720. The electrical terminal 722 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 724 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The battery cell 192 has a rectangular-shaped housing 730 withelectrical terminals 732, 734 extending from first and second ends,respectively, of the housing 730. The electrical terminal 732 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 734 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The battery cell 196 has a rectangular-shaped housing 740 withelectrical terminals 742, 744 extending from first and second ends,respectively, of the housing 740. The electrical terminal 742 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 744 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

The battery cell 200 has a rectangular-shaped housing 750 withelectrical terminals 752, 754 extending from first and second ends,respectively, of the housing 750. The electrical terminal 752 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 220. The electrical terminal 754 iselectrically and physically coupled to the battery cell interconnect andvoltage sensing assembly 222.

Referring to FIG. 6, the end plates 230, 232 are provided to guidecooling air through the flow path portions 540, 574, 584 of the framemembers 120, 124, 128, respectively. The end plates 230, 232 have theframe members 120-128 and the battery cells 150-200 disposedtherebetween.

The end plate 230 extends substantially parallel to a longitudinal axis768 of the battery module 34. The end plate 230 has a first end portion770 and a second end portion 772. The first end portion 770 extendslongitudinally past a first end of each of the battery cells 150-170toward the inlet aperture 112. The second end portion 772 extendslongitudinally past the second end of each of the battery cells 180-200.

The end plate 232 extends substantially parallel to the longitudinalaxis 768 of the battery module 34. The end plate 232 has a first endportion 780 and a second end portion 782. The first end portion 780extends longitudinally past a first end of each of the battery cells150-170 toward the inlet aperture 112. The second end portion 782extends longitudinally past the second end of each of the battery cells180-200.

Referring to FIGS. 5, 6 and 23-26, the thermally conductive housing 38is provided to hold the DC/DC voltage converter 42 therein that iselectrically coupled to the battery cells of the battery module 34. Thethermally conductive housing 38 transfers heat from the DC/DC voltageconverter 42 to air flowing past the thermally conductive housing. Thethermally conductive housing 38 is disposed in the interior space 78 ofthe interior region 74 of the battery pack housing 30 between thebattery module 34 and the outlet aperture 114 of the battery packhousing 30. The thermally conductive housing 38 defines a flow pathportion 804 between the thermally conductive housing 38 and the batterypack housing 30. The flow path portion 804 fluidly communicates with theflow path portions 540, 574, 584 of the battery module 34 and with theoutlet aperture 114.

The thermally conductive housing 38 includes a housing portion 800 and aframe member 802. The housing portion 800 includes bottom wall 810 andcooling fins 820, 822, 824, 826, 840, 842, 844, 846, 848 extendingoutwardly from the bottom wall 810 in a first direction. The coolingfins 820-848 are spaced apart from one another such that the flow pathportion 804 is defined between the cooling fins 820-848. The coolingfins 820-848 are disposed on the bottom wall 90 (shown in FIG. 5) of thebase portion 70. In an exemplary embodiment, the thermally conductivehousing 38 is constructed of aluminum. Of course, in an alternativeembodiment, the thermally conductive housing 38 can be constructed ofother materials such as steel or other metal alloys for example.

Referring to FIGS. 6 and 23, the frame member 802 is coupled to anexterior of the thermally conductive housing 38 and includes an outletportion 870 that directs air toward the fan 46 and the outlet aperture114 of the battery pack housing 30.

Referring to FIGS. 5 and 6, the electric fan 46 is disposed in theinterior region 74 of the battery pack housing 30 proximate to theoutlet aperture 114 of the battery pack housing 30. The electric fan 46is adapted to urge air to flow through the inlet aperture 112 andthrough the flow path portions 540, 574, 584 of the battery module andthe flow path portion 804 and further through a portion of the electricfan 46 and through the outlet aperture 114 of the battery pack housing30. In an alternative embodiment, the electric fan 46 is disposedproximate to the inlet aperture 112.

Referring to FIGS. 6, 14, 16, 17 and 27, a flowchart of a method ofassembling a portion of the battery module 34 in accordance with anotherexemplary embodiment is provided.

At step 900, a user provides the battery cells 154, 184. After step 900,the method advances to step 902.

At step 902, the user provides the frame member 120 having thesubstantially rectangular ring-shaped outer plastic frame 260 and theheat exchanger 264. The heat exchanger 264 has first and secondthermally conductive plates 360, 362 that are coupled together anddefine a flow path portion 540 (shown in FIG. 17) extendingtherethrough. The flow path portion 540 has at least flow pathsubportions 554, 558 extending through the first and second thermallyconductive plates 360, 362. The substantially rectangular ring-shapedouter plastic frame 260 is coupled around an outer peripheral region ofthe first and second thermally conductive plates 360, 362. Thesubstantially rectangular ring-shaped outer plastic frame 260 has first,second, third, and fourth side walls 280, 282, 284, 286. The first andsecond side walls 280, 282 extend substantially parallel to one another.The third and fourth side walls 284, 286 are coupled between the firstand second side walls 280, 282 and extend substantially parallel to oneanother and perpendicular to the first and second side walls 280, 282.The first side wall 280 has apertures 302, 304 (shown in FIG. 14)extending therethrough that communicate with the flow path subportions554, 558, respectively. The second side wall 282 has apertures 312, 314(shown in FIG. 17) extending therethrough that communicate with the flowpath subportions 554, 558, respectively. After step 902, the methodadvances to step 904.

At step 904, the user disposes the battery cell 154 on and against afirst side of the first thermally conductive plate 360 of the heatexchanger 264. After step 904, the method advances to step 906.

At step 906, the user disposes the battery cell 184 on and against thefirst side of the first thermally conductive plate 360 of the heatexchanger 264. The battery cell 184 is further disposed proximate to thebattery cell 154. After step 906, the method advances to step 908.

At step 908, the user provides battery cells 158, 188 and the framemember 124 having the heat exchanger 572. After step 908, the methodadvances to step 910.

At step 910, the user disposes the battery cell 158 on and against thebattery cell 154. After step 910, the method advances to step 912.

At step 912, the user disposes the battery cell 188 on and against thebattery cell 184. After step 912, the method advances to step 914.

At step 914, the user disposes the heat exchanger 572 on the batterycells 158, 188.

Referring to FIGS. 2, 6 and 28, a flowchart of a method of assemblingthe battery pack 10 in accordance with another exemplary embodiment isprovided.

At step 930, the user provides the battery pack housing 30, the batterymodule 34, the thermally conductive housing 38, and the electric fan 46.The battery pack housing 30 defines the interior region 74. The batterypack housing 30 further includes the inlet aperture 112 and the outletaperture 114 communicating with the interior region 74. The batterymodule 34 has the battery cell 154, the heat exchanger 264, and endplates 230, 232. The battery cell 154 and the heat exchanger 264 aredisposed against one another, and are further disposed between the endplates 230, 232. The heat exchanger 264 defines a flow path portion 540therethrough. The battery cell 154 has a first end and a second end. Theend plate 230 extends substantially parallel to the longitudinal axis768 of the battery module 34. The end plate 230 has the first endportion 770 and the second end portion 772. The first end portion 770 ofthe end plate 230 extends longitudinally past the first end of thebattery cell 154. The second end portion 772 of the end plate 230extends longitudinally past the second end of the battery cell 154. Theend plate 232 extends substantially parallel to the longitudinal axis768 of the battery module 34. The end plate 232 having the first endportion 780 and the second end portion 782. The first end portion 780 ofthe end plate 232 extends longitudinally past the first end of thebattery cell 154. The second end portion 782 of the end plate 232extends longitudinally past the second end of the battery cell 154.After step 930, the method advances to step 932.

At step 932, the user disposes the battery module 34 in the interiorregion 74 of the battery pack housing 30 proximate to the inlet aperture112. After step 932, the method advances to step 934.

At step 934, the user disposes the thermally conductive housing 38 inthe interior region 74 of the battery pack housing 30 between thebattery module 34 and the outlet aperture 114 of the battery packhousing 30. The thermally conductive housing 38 defines the path portion804 between the thermally conductive housing 38 and the battery packhousing 30. The flow path portion 804 fluidly communicates with the flowpath portion 540. After step 934, the method advances to step 936.

At step 936, the user disposes the electric fan 46 in the interiorregion 74 of the battery pack housing 30 proximate to the outletaperture 114 of the battery pack housing 30. The electric fan 46 isadapted to urge air to flow through the inlet aperture 112 and throughthe path portions 540, 804 and further through a portion of the electricfan 46 and through the outlet aperture 114 of the battery pack housing30.

The battery pack and the method of assembling the battery pack provide asubstantial advantage over other battery packs and methods. Inparticular, the battery pack and the method utilize a battery modulewith first and second end plates that extend past ends of a battery cellto direct air into a heat exchanger disposed against the battery cell tocool the battery module.

While the claimed invention has been described in detail in connectionwith only a limited number of embodiments, it should be readilyunderstood that the invention is not limited to such disclosedembodiments. Rather, the claimed invention can be modified toincorporate any number of variations, alterations, substitutions orequivalent arrangements not heretofore described, but which arecommensurate with the spirit and scope of the invention. Additionally,while various embodiments of the claimed invention have been described,it is to be understood that aspects of the invention may include onlysome of the described embodiments. Accordingly, the claimed invention isnot to be seen as limited by the foregoing description.

What is claimed is:
 1. A battery pack, comprising: a battery packhousing having a base portion and an upper cover; the base portion andthe upper cover defining an interior region when the upper cover iscoupled to the base portion, the base portion having a bottom wall andfirst and second side walls coupled to the bottom wall, the first sidewall having an inlet aperture extending therethrough that communicateswith the interior region, the second side wall having an outlet apertureextending therethrough that communicates with the interior region; abattery module being disposed in the interior region of the battery packhousing proximate to the inlet aperture, the battery module having afirst battery cell, a first frame member, and first and second endplates; the first frame member having a first rectangular ring-shapedouter plastic frame and a first aluminum heat exchanger, the firstrectangular ring-shaped outer plastic frame being coupled around anouter peripheral region of first and second thermally conductive platesof the first aluminum heat exchanger, the first rectangular ring-shapedouter plastic frame having first, second, third, and fourth walls; thefirst and second walls extending parallel to one another; the third andfourth walls extending parallel to one another and perpendicular to thefirst and second walls; the first wall having first, second, and thirdapertures extending therethrough with the second aperture thereof beingdisposed between the first and third apertures thereof; the second wallhaving first, second, and third apertures extending therethrough withthe second aperture thereof being disposed between the first and thirdapertures thereof; the first and second thermally conductive aluminumplates being coupled together and directly contacting one another suchthat the first and second thermally conductive aluminum plates define afirst flow path portion therebetween, the first flow path portionfluidly communicating with the first, second, and third apertures of thefirst wall of the first rectangular ring-shaped outer plastic frame andwith the first, second, and third apertures of the second wall of therectangular ring-shaped outer plastic frame; the first battery cell andthe first aluminum heat exchanger being disposed against one another,and being further disposed between the first and second end plates; thefirst battery cell having a first end and a second end; the first endplate extending substantially parallel to a longitudinal axis of thebattery module, the first end plate having a first end portion and asecond end portion, the first end portion of the first end plateextending longitudinally past the first end of the first battery celltoward the inlet aperture, the first end portion of the first end platecontacting the first side wall of the base portion above the inletaperture and a first distance below a top end of the first side wall;the second end portion of the first end plate extending longitudinallypast the second end of the first battery cell; the second end plateextending substantially parallel to the longitudinal axis of the batterymodule, the second end plate having a first end portion and a second endportion, the first end portion of the second end plate extendinglongitudinally past the first end of the first battery cell toward theinlet aperture; the second end portion of the second end plate extendinglongitudinally past the second end of the first battery cell, the firstend portion of the second end plate contacting the first side wall ofthe base portion below the inlet aperture and a second distance above abottom end of the first side wall; the second end plate being disposedaway from the first end plate, and the first end portion of the firstend plate and the first end portion of the second end plate forming achannel for routing air from the inlet aperture into the first, second,and third apertures in the first wall of the first rectangularring-shaped outer plastic frame, and into the first flow path portion ofthe first aluminum heat exchanger; a thermally conductive housing beingdisposed in the interior region of the battery pack housing between thebattery module and the outlet aperture of the battery pack housing; thethermally conductive housing defining a second flow path portion betweenthe thermally conductive housing and the battery pack housing, thesecond flow path portion communicating with the first flow path portion;and an electric fan disposed in the interior region of the battery packhousing; the electric fan adapted to urge the air to flow through theinlet aperture of the battery pack housing and through the first andsecond flow path portions and further through a portion of the electricfan and through the outlet aperture of the battery pack housing.
 2. Thebattery pack of claim 1, wherein the thermally conductive housing havinga bottom wall and a plurality of cooling fins extending outwardly fromthe bottom wall thereof and spaced apart from one another such that thesecond flow path portion is at least partially defined between theplurality of cooling fins.
 3. The battery pack of claim 2, wherein thethermally conductive housing holds a DC/DC voltage converter that iselectrically coupled to the first battery cell of the battery module. 4.The battery pack of claim 3, wherein the battery module being disposedon the bottom wall of the base portion, and the plurality of coolingfins of the thermally conductive housing being disposed on the bottomwall of the base portion.
 5. The battery pack of claim 2, wherein thethermally conductive housing is constructed of aluminum.
 6. The batterypack of claim 1, wherein the first battery cell is disposed against afirst side of the first aluminum heat exchanger, the battery modulefurther having a second battery cell disposed against the first side ofthe first aluminum heat exchanger.
 7. The battery pack of claim 1,wherein the first flow path portion having at least first and secondflow path subportions extending through the first and second thermallyconductive plates.
 8. The battery pack of claim 7, wherein the firstbattery cell being disposed against a first side of the first thermallyconductive plate of the first aluminum heat exchanger, the battery packfurther comprising a second battery cell being disposed against thefirst side of the first thermally conductive plate of the first aluminumheat exchanger.
 9. The battery pack of claim 1, wherein the electric fanis further disposed proximate to the outlet aperture of the battery packhousing.
 10. The battery pack of claim 1, wherein the base portionfurther includes third and fourth side walls; the first, second, thirdand fourth side walls are coupled to the bottom wall and extend upwardlysubstantially perpendicular to the bottom wall, the first and secondside walls extend substantially parallel to one another, the third andfourth side walls extend substantially parallel to one another andperpendicular to the first and second side walls.
 11. The battery packof claim 1, wherein the battery module further includes a second batterycell and a second frame member, the second frame member having a secondaluminum heat exchanger; the second battery cell being disposed againstand between the second aluminum heat exchanger and the first batterycell; the second battery cell and a second aluminum heat exchanger beingfurther disposed between the first and second end plates; the secondaluminum heat exchanger defining a third flow path portion therethroughthat extends substantially parallel to the first flow path portion. 12.The battery pack of claim 11, wherein the first and third flow pathportions of the first and second aluminum heat exchangers, respectively,extend substantially parallel to the longitudinal axis of the batterymodule, such that the air flows substantially longitudinally through thefirst and second aluminum heat exchangers.
 13. The battery pack of claim11, wherein the first battery cell is a pouch-type lithium-ion batterycell having a substantially rectangular-shaped body that is disposed onand against the first aluminum heat exchanger, the second battery cellis a pouch-type lithium-ion battery cell having a substantiallyrectangular-shaped body that is disposed on and against the secondaluminum heat exchanger.
 14. A battery pack, comprising: a battery packhousing having a base portion and an upper cover; the base portion andthe upper cover defining an interior region when the upper cover iscoupled to the base portion, the base portion having a bottom wall andfirst and second side walls coupled to the bottom wall, the first sidewall having an inlet aperture extending therethrough that communicateswith the interior region, the second side wall having an outlet apertureextending therethrough that communicates with the interior region; abattery module being disposed in the interior region of the battery packhousing proximate to the inlet aperture, the battery module having afirst battery cell, a second battery cell, first and second framemembers, and first and second end plates; the first frame member havinga first rectangular ring-shaped outer plastic frame and a first aluminumheat exchanger, the first rectangular ring-shaped outer plastic framebeing coupled around an outer peripheral region of first and secondthermally conductive plates of the first aluminum heat exchanger; thefirst rectangular ring-shaped outer plastic frame having first, second,and third apertures extending through a first wall thereof with thesecond aperture being disposed between the first and third apertures;the first rectangular ring-shaped outer plastic frame having fourth,fifth, and sixth apertures extending through a second wall thereof withthe fifth aperture being disposed between the fourth and sixthapertures; the first and second thermally conductive aluminum platesbeing coupled together and directly contacting one another such that thefirst and second thermally conductive aluminum plates define a firstflow path portion therebetween; the second frame member having a secondrectangular ring-shaped outer plastic frame and a second aluminum heatexchanger, the second aluminum heat exchanger having first and secondthermally conductive aluminum plates coupled together that define asecond flow path portion therebetween; the first battery cell and thefirst aluminum heat exchanger being disposed against one another, andbeing further disposed between the first and second end plates; thefirst battery cell having a first end and a second end; the secondbattery cell being disposed against and between the second aluminum heatexchanger and the first battery cell; the second battery cell and asecond aluminum heat exchanger being further disposed between the firstand second end plates; the second battery cell having a first end and asecond end; the first end plate extending substantially parallel to alongitudinal axis of the battery module, the first end plate having afirst end portion and a second end portion, the first end portion of thefirst end plate extending longitudinally past both the first end of thefirst battery cell and the first end of the second battery cell towardthe inlet aperture, the first end portion of the first end platecontacting the first side wall of the base portion above the inletaperture and a first distance below a top end of the first side wall;the second end portion of the first end plate extending longitudinallypast both the second end of the first battery cell and the second end ofthe second battery cell; the second end plate extending substantiallyparallel to the longitudinal axis of the battery module, the second endplate having a first end portion and a second end portion, the first endportion of the second end plate extending longitudinally past the firstend of the first battery cell and the first end of the second batterycell toward the inlet aperture; the second end portion of the second endplate extending longitudinally past the second end of the first batterycell and the second end of the second battery cell, the first endportion of the second end plate contacting the first side wall of thebase portion below the inlet aperture and a second distance above abottom end of the first side wall; the second end plate being disposedaway from the first end plate, and the first end portion of the firstend plate and the first end portion of the second end plate forming achannel for routing the air from the inlet aperture into the first,second, and third apertures of the first wall of the first rectangularring-shaped outer plastic frame and into the first flow path portion ofthe first aluminum heat exchanger, and routing the air from the inletaperture into the second flow path portion of the second aluminum heatexchanger; a thermally conductive housing being disposed in the interiorregion of the battery pack housing between the battery module and theoutlet aperture of the battery pack housing; the thermally conductivehousing having a bottom wall and a plurality of cooling fins extendingoutwardly from the bottom wall and spaced apart from one another suchthat a third flow path portion is at least partially defined between theplurality of cooling fins, the third flow path portion communicatingwith the first and second flow path portions; and an electric fandisposed in the interior region of the battery pack housing; theelectric fan adapted to urge the air to flow through the inlet apertureof the battery pack housing and through the first, second, and thirdflow path portions and further through a portion of the electric fan andthrough the outlet aperture of the battery pack housing.
 15. The batterypack of claim 14, wherein the first and second flow path portions of thefirst and second aluminum heat exchangers, respectively, extendsubstantially parallel to the longitudinal axis of the battery module,such that the air flows substantially longitudinally through the firstand second aluminum heat exchangers.
 16. The battery pack of claim 14,wherein the first battery cell is a pouch-type lithium-ion battery cellhaving a substantially rectangular-shaped body that is disposed on andagainst the first aluminum heat exchanger, the second battery cell is apouch-type lithium-ion battery cell having a substantiallyrectangular-shaped body that is disposed on and against the secondaluminum heat exchanger.
 17. The battery pack of claim 1, wherein avertical length of the inlet aperture in the first side wall is greaterthan a combined vertical length of the first battery cell and the firstaluminum heat exchanger.
 18. The battery pack of claim 14, wherein avertical length of the inlet aperture in the first side wall is greaterthan a combined vertical length of the first and second battery cellsand the first and second aluminum heat exchangers.
 19. The battery packof claim 1, wherein: the first thermally conductive plate having firstand second elongated depressed portions disposed apart from another; thesecond thermally conductive plate having first and second elongateddepressed portions disposed apart from another; and the first and secondelongated depressed portions of the second thermally conductive platebeing disposed directly against the first and second elongated depressedportions, respectively, of the first thermally conductive plate suchthat at least a portion of the first flow path portion is definedbetween the first and second elongated depressed portions of the firstthermally conductive plate and between the first and second elongateddepressed portions of the second thermally conductive plate.
 20. Thebattery pack of claim 14, wherein: the first thermally conductive platehaving first and second elongated depressed portions disposed apart fromanother; the second thermally conductive plate having first and secondelongated depressed portions disposed apart from another; and the firstand second elongated depressed portions of the second thermallyconductive plate being disposed directly against the first and secondelongated depressed portions, respectively, of the first thermallyconductive plate such that at least a portion of the first flow pathportion is defined between the first and second elongated depressedportions of the first thermally conductive plate and between the firstand second elongated depressed portions of the second thermallyconductive plate.